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establishing dope

firefightinlv

Private
Full Member
Minuteman
Mar 30, 2010
6
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50
What is the best way of gathering dope on a new round. I have a 500 yard range and looking for advice on a zero for a point blank. the round is a 150gn FMJBT loaded with benchmark powder and chronos at 2750 fps. Lookin at advice to build a ballistics table. Thanks!
 
Re: establishing dope

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">Go to JBM Ballistics, which is a free ballistics calculator on the net, and put in your numbers and it will give you data to get you on paper or better.

Here's a link
http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi </div></div>

Rob,

I had always understood "dope" to be synonymous with field data, which could be (hopefully) easily obtained with the help of ballistics data from a program like JBM. The important difference of course that field data was verified.

Not true?

John
 
Re: establishing dope

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jrob300</div><div class="ubbcode-body">I had always understood "dope" to be synonymous with field data, which could be (hopefully) easily obtained with the help of ballistics data from a program like JBM. The important difference of course that field data was verified.</div></div>

In terms of dope, the accurate ballistics programs are simpy ways to initialize the unknown entries in the dope book. Once real dope shows up, it takes precidence.
 
Re: establishing dope

Of course field data is the best to have as that is actually what your rifle is doing with the load and also with the scope as some scopes don't track 100% perfect. That said if he has no data but has his velocity a good ballistics program will get him on paper and then he can adjust that little bit to be right on. I use JBM for my match data and out to 500 yards it's always been right on. Even to 1000 it's only been of around .2 mils.

Data, dope, come ups etc are just words for what you need to adjust the scope to hit the target at any certain range.

To the OP, I would recommend a 100 yard zero on a precision rifle and learn your data from there. From a 100 yard zero anything you dial will be up, even when you come in to 50, 25 etc, so no chance of getting lost on the dial.
 
Re: establishing dope

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">

To the OP, I would recommend a 100 yard zero on a precision rifle and learn your data from there. From a 100 yard zero anything you dial will be up, even when you come in to 50, 25 etc, so no chance of getting lost on the dial. </div></div>

+1

Point blank zero has a specific use and you will learn and have easier use out of a standard 100 yrd zero.